Port St. Lucie is a city in St. Lucie County, Florida, United States. It is the most populous municipality in the county with a population of 164,603 at the 2010 census due to its rapid growth during the 2000s. It is located 125 mi southeast of Orlando, and 114 mi northwest of Miami. In 2018, the United States Census Bureau estimated the city's population at 195,248. The Port St. Lucie Metropolitan Area includes the counties of St. Lucie County & Martin County and as of 2016 had an estimated population of 465,208. Port St. Lucie is also contained within the Miami - Fort Lauderdale - Port St. Lucie Combined Statistical Area with an estimated population of 6,832,588.